1. Field of the Invention
The present invention relates to a solid-state imaging device and a camera, and particularly relates to a MOS (metal-oxide semiconductor) solid-state imaging device and camera.
2. Description of the Related Art
Solid-state imaging devices include a charge-transfer solid-state imaging device represented by a CCD (charge-coupled device) image sensor and an amplification solid-state imaging device represented by a MOS (metal-oxide semiconductor) image sensor such as a CMOS (complementary metal-oxide semiconductor) image sensor. When comparing the CCD image sensor with the MOS image sensor, the CCD image sensor may need a high driving voltage to transfer signal electric charges, so that a power supply voltage for the CCD image sensor may be higher than that of the MOS image sensor.
Accordingly, a mobile phone unit incorporating a camera, a PDA (personal digital assistant) and other mobile devices typically use a CMOS image sensor as a solid-state imaging device mounted thereon. The CMOS image sensor is advantageous in that a power supply voltage is lower than that of the CCD image sensor and power consumption is lower than that of the CCD image sensor.
For insulating and isolating elements, a LOCOS (local oxidation of silicon) (selective oxidation) element isolation system or a STI (shallow trench isolation) element isolation system is known as an element isolation system used in the MOS image sensor (see Japanese Unexamined Patent Application Publication No. 2002-270808). In particular, the STI element isolation system has been widely used with pixels increasingly miniaturized.
In a solid-state imaging device, the number of pixels has been increased along with the resolution being improved, and a pixel is further miniaturized because the solid-state imaging device includes a large number of pixels.